Navitas’ integrated GaN solutions (GaNFast) enables electric charging systems to operate up to 100 times faster than those with conventional silicon components by offering five times higher power density, 40 percent more energy savings, and 20 percent less on production costs. You’ll be able to recharge your smartphones a lot faster, for example.

The initial market adoption of power gallium nitride (GaN) in mid-to-late 2018 in the aftermarket space was with 24- to 65 watt chargers from Anker, Aukey and RAVpower. In 2019 we’ve seen additional accessory releases and now ‘in-box’ adoption from 27- to 300 watts by OEMs such as Samsung, Verizon, Oppo and Asus/Nvidia with multi-millions of units shipped.

GaN is a new production semiconductor that is expected to replace silicon in many applications in the coming years, and battery charging is the first high-volume market to demonstrate such adoption. Nowadays, most of the chargers being used for electronic products use silicon transistors, and for years this has been the best solution for efficiency and size. Silicon is gradually reaching its physical limits, especially with regard to power density; that in turn limits how compact a device equipped with silicon power components can be. GaN has a superior performance compared to silicon at very high voltages, temperatures, and switching frequencies, thus allowing a significantly higher energy efficiency.

 

Figure 1: Smartphone Screen Size (cm2) and Battery Capacity (mAhr) 2007-2019

The continued demand for more powerful smartphones, tablets, and laptops with larger screens and 5G features has created a market for the next generation of AC adapters to charge larger and larger Li-ion batteries very quickly (Figure 1).

As silicon power devices are swapped out for GaN replacements, the days when we’re compelled to carry huge electric bricks and multiple cables to run our devices may end. The time we wait to charge smartphones and laptop could be significantly reduced, and the surprisingly hot charger may be a thing of the past. With a multitude of chargers and GaN adapters ranging from 27W to 300W in mass production, powering everything from phones to drones, the mobile charger market is set to change dramatically.

“People want faster charging for their mobile devices, which means more power is needed but they don’t want the large size and weight of a silicon-based adapter. Phones have increased from only 5-watt charging a few years ago to 50 watts or more on high-end, premium phones today, and with up to 120 watts claimed for new platforms. Laptops are already 50 – 60 watts with big, bulky chargers, and GaN is a big opportunity to deliver that high-power fast-charging, but in a dramatically smaller and lighter-weight form-factor,” said Gene Sheridan, Navitas CEO.

After years of academic research on discrete GaN in the 1990s, and integrated GaN in the 2000s, GaNFast power integrated circuits are now the industry-proven, commercially-attractive, next-generation solution to design smaller, lighter, faster chargers and power adapters.

“GaN is very good around 600 volts, dramatically better than silicon in terms of chip area, circuit efficiency & switching frequency, so it’s a very nice sweet-spot to use GaN to replace silicon in these wall chargers,” said Sheridan. “The combination of soft-switching topologies with our GaN ICs dramatically improves efficiency. Using a mobile charger example, with silicon and a traditional flyback topology, efficiency was only 87-89%. With GaN in a soft-switching topology, we’re looking at 93-95%.”

Single and half-bridge GaNFast power ICs are 650V GaN-on-Si FETs with monolithic integration of drive and logic, packaged in quad flat no-lead (QFN) packages. GaNFast technology allows switching frequencies up to 10 MHz which enables the use of smaller & lighter passive components. The monolithic integration of a field-effect transistor (FET), drive, and logic creates an easy-to-use constituent component that allows designers to create an ultra-fast, ultra-compact, and ultra-efficient integrated powertrain.

Integration is key to minimize delays and eliminate parasitic inductances that have restricted the switching speed of Si and earlier discrete GaN circuits. With propagation delays down to 5 ns, and robust dV/dt up to 200 V/ns, traditional 65-100 kHz converter designs can be accelerated to MHz and beyond. These integrated circuits extend the capabilities of traditional topologies such as flyback, half-bridge, resonant and others, at frequencies of the order of MHz, allowing the commercial introduction of revolutionary projects (figure 2).

 

Figure 2: integration of GaNFast [Source: Navitas]

GaNFast technology will also soon make its way into the world’s fastest laptop: the Asus ProArt StudioBook One. ProArt One, an NVIDIA RTX Studio system, is the first laptop to feature the NVIDIA Quadro RTX 6000 GPU and is based on NVIDIA’s ACE reference architecture. Developed in collaboration with NVIDIA, the new 300W AC-DC design leverages Navitas’ high-speed GaNFast power IC power conversion technology to create a powerful yet lightweight and small portable charger.

“Creatives and other professionals demand the highest computing performance with extreme mobility,” said Sheridan. “Navitas’ dedicated technologists worked alongside the NVIDIA engineering design team to address this challenge as part of the NVIDIA ACE reference design, delivering a 300 watt laptop adapter in less than half the size and weight,” he added.

Figure 3: the inside of a battery charger with GaNFast technology

GaN solutions enable you to develop more efficient and compact adapter designs. It provides the world’s fastest transistors, which are essential for ultra-efficient power conversion. The new technology reduces the size of power electronics by more than 50%, making it possible to create true universal battery chargers for mobile devices. Using GaN semiconductors, you can create chargers that are not only more efficient but also deliver the same power in a much smaller footprint than traditional chargers. These power supplies stay cooler – there is much less dissipation, and they require fewer components and are also cheaper (Figure 3).